Hand-operated sprayer or the like



Aug. 23, 1960 P. o. EsMAY 2,950,153

HAND-OPERATED SPRAYER 0R THE LIKE Filed Jan. l2, 1959 2 Sheets-Sheet l Aug, 23, 1960 n P. o. ESMAY 2,950,153

HAND-OPERATBD SPRAYER 0R THE LIKE Filed Jan. 12, 1959 v 2 sheets-sheet 2 Patented Aug. 23, 1960 HAND-@PERATED SPRAYEB OR THE LIKE Paul i). Esmay, 1600 Main St., Three vers, Mich.

Filed Jan. l2, 1959, Ser. No. 786,064

l Claims. (Cl. 309-23) This application is a continuation-in-part of application Ser. No. 638,524, entitled Garden Spray Gun, iiled February 6, i957, now Patent No. 2,880,936.

This invention relates to hand-operated spray devices, such as sprayers for dispensing garden chemicals and the like, although some aspects of the invention have a broader application in reciprocating devices of both handoperated and machine-driven types, such as pumps and other reciprocating devices where a piston, plunger, or their reciprocating member makes pressure sealing engagement with the walls of a cylinder or bore therein. More particularly, the invention relates to a reciprocating device, most preferably a hand-operated sprayer or similar device including a novel pressure sealing means between the relatively movable parts thereof where a sliding, pressure sealing engagement therebetween takes place, such as between a piston or plunger and the walls of the piston cylinder or plunger bore. The sealing means has particular utility in a hand-operated sprayer or similar pumping device where it forms a pressure seal in one direction of movement of the piston or plunger thereof and an open valve in the other direction of movement thereof where a fluid, such as air, passes around the sealing means.

Hand-operated spray devices are, in general, extremely tedious to operate due, in part, to the manner in which the pistons or plungers thereof make sliding engagement with the walls of the piston cylinder or plunger bore. Generally, in these hand-operated sprayers, a compromise must be made between the requirements of a good pressure seal on the one hand, and minimum frictional drag on the other hand. The requirement of a good seal is generally a paramount requirement, with the result that such sprayers are usually relatively diiiicult to operate.

It is, accordingly, an object of the present invention to provide a reciprocating device, particularly, although not necessarily, a hand-operated sprayer or the like wherein, in at least one direction of movement thereof, a rugged, highly effective pressure seal is maintained hetween relatively reciprocating -parts thereof, such as between a piston or plunger and the walls of the cylinder or bore in which the piston or plunger is reciprocated and, at the same time, the resultant frictional drag is so small that the piston or plunger or other reciprocating part could be easily manually operated or otherwise driven with a relatively small amount of force.

It is another object of the present invention to provide a reciprocating device, most particularly a hand-operated device, which includes a sealing unit carried thereby which, in one direction of movement of a piston or plunger thereof, makes a highly elective seal while requiring a minimum of force to move the same, and, in the other direction of movement thereof, provides a one- Way valve which readily ilexes to allow passage therearound of air, water or other uid.

In accordance with one aspect of the present invention, one of the relatively reciprocating members of the reethylene film or similar material. The stack of discs are arranged so that the longitudinal axis thereof is parallel to the direction of movement of the reciprocating member. tively reciprocating members and are provided with at least one rigid backing extending close to but still spaced from said other member. The latter spacing is such that the exure of the stack of discs as a whole into the space between the backing and said other part is prevented. lf a seal is to be elfected in both directions of movement of the reciprocating member, a rigid backing as described is placed at both ends of the stack of discs. In this application of the invention, the stack of discs may form a packing gland between a plunger or piston rod and the dening walls of an opening in the body of the device into which the rod extends, or a two-way sealing ring carried by a pump piston.

The ilexibility of the discs resulting from the thinness and the material out of which they are made enables a substantially closer fit between the discs and the walls of the part with which it makes sliding engagement than would be possible with a sealing unit made from a single piece of material having a thickness equivalent to the stack of discs, so that substantially greater sealing action is obtained for a sealing unit of a given thickness. Moreover, since the discs are arranged in random fashion in the stack, any defect which may be present in one angular position of a disc will not necessarily result in a break-down ofthe seal provided by the stack of discs as a whole, -since it is highly unlikely that the other discs would be defective, if at all, at the same angular point. Also, both the iiexibility of the discs'and the slippery nature of the polyethylene or similar type material greatly reduce frictional drag. Since the above-mentioned characteristics of the stack of discs provide for increased sealing capabilities over a sealing unit made from one or a few pieces of much thicker and dierent materal, much less area of contact is required between the sealing discs and the walls with which they make sliding engagement for a pressure seal of a given quality, further minimizing the frictional drag.

In accordance with another aspect of the invention, the stack of discs above described is carried by the piston or plunger of a sprayer or similar pumping device and is provided with a rigid backing as above described on only one side. The flexibility of the discs enables them to act as an open valve when moved a direction away from the unbacked side of the stack of discs. The backing, of course, must be spaced from the walls of the piston cylinder or plunger bore a suicient amount to enable a suti'icient quantity of'the Huid involved to pass around the sealing unit, or otherwise provided with suitable peripheral pass-through slots for the fluid.

Other objects, advantages and features of the invention will become apparent upon making reference to the specifications to follow, the claims and the drawings wherein:

Fig. l is a perspective View or" a hand-operated garden sprayer which incorporates features of the present invention;

Fig. 2 is an enlarged longitudinal sectional View ot the sprayer of Fig. l, taken along section line 2-2 therein, and showing the plunger tube being moved upward within the outer tube, the arrows therein showing the path of movement of air and material to be sprayed into the pumping space thereof;

Fig. 3 is a fragmentary longitudinal sectional View corresponding to Fig. 2, showing the position of the' The discs slidingly engage the other of said rela- Ythe bottom of the wen 34.

plunger tube Vand the path of iiuid flow during the compression stroke of the plunger tube;

Fig. 4 is a view corresponding to the View of Fig..3 showing the bottom-.of the plunger tube-inltcontact with the bottom Lof the outerftube and the con'sequentopening of the dispensing valvev atthe bottoml of the plunger tube when ,the receiving wall is iilledwith a finite quantity offluid; Y Y Y *Y Y e A ig. 5 is a fragmentary enlarged viev/,of therbotto-rn i end of. the plunger tube showing the valve and sealing discs of the. present invention attachedV to the and thereof;

Fig. 6V is an exploded view of Vthe valve and sealing Y disc assembly ofthe present inventiong' Fig. 7 is an enlarged longitudinal fragmentary sectional view of aV reciprocating device utilizingthe sealing unit of the present' invention on a plunger, and also as a packing gland around aplunger rod; Y l

Fig.. 8Iis ar transverse sectional VVView, partly broken away, through the reciprocating device shown in Fig. 7,

' taken alongrsection line S-S'in Fig. 7;,and

Fig. 9 is a plan view of one of the sealing discs making up thesealing unit of Fig. 7. ,Y Y

' Figs. 1-6 illustrate a sprayer for garden chemicals comprising an outer elongated, Vcylindrical Vtube i@ made preferably` of a transparent plastic material, suchV as Tenite Butyrate, a mixed ester composition made by Eastman Chemical Products, lne., and an. inner Yelongated cylindrical plunger tube 12 carrying the supply of material to be sprayed and made of the same transparent material and having a length of theV same order of mag-v nitude'/v as the outer tube. The Vplunger tube 12 is recip-v rocally mounted within the outer tube it? forming a guide ing means l5 closes and makes a highly effective'pressure sealing engagement with the walls of the vuter tube 19, Y so that the plunger tube forces the material to be sprayedV .in atomized form through a dischargev orifice 18 formed, p in a domeshaped end cap ZtlV connected tothe bottom end of the ontertube it?. VNow that the overall make-up and operation ofi Ythe sprayV device. has beenV briefly explained, the' detailed construction of the various cornponents making up the sprayer-Will'be described.

Referring now `more particularly to Figs. 2-5, thel plungerl'tube 12 has "an outeridiameterrsomewhat smaller than the inner diameter of the' outer tube 1i? so the former fits loosely' Within the latter to provideran material. The valve stem 35 has a rubber valve headV 36 snugly applied thereover and held upon the stem by a preferably plastic washer 36' which in turn is held upon the stem by a metal snap ring 37 extending Within an annular grooveformed around the valve stem 35. At the bottom end ofthe valve stem there is provided an inverted, anged' metalr cup-shaped member 3g which snugly surrounds the valve stem and is held thereupon'by a metal snap ring 39 litting within an annular groove formed in the valve stem. The member 38 has a peripheral flange thereon forming a shoulder for receiving the Vbottomf end of ametalV coilcompression spring 4l whose upper end bears against a preferably plastic washer 42 which contacts the valve and sealing means 15 to hold the same in place upon the plunger tube. The spring 4i urges the valve stem 35 downward and hence the valve head 36 upon the bottom of the valve seat recess 3i, closingoffthe yopening betweenthe Well 34 l andthe compartment within the plunger tube i2 containingthe material to be sprayed. t Y Y, t Y ln accordance with theppresent invention, the yalve and sealing means 15 comprises a stack ofyeryfthin, circular, flat wafer-like discs 43 or thelike, each Vmade of a iiexible, somewhat slippery material, Vwhich is `most advantageously Ypolyetliylene or similar synthetic plastic materiah Thicknesses 'ofVv the order of from .Q04 to .097 inch have been foundtoY be especially satisfactory. Sheetsv of material vof'such FthinnessV are often referred to as nlmA or Yhaving Vthe thinness of lilrn.` The discs are each provided with arelatively large central reces'sr45, the dening Walls of which lit snugly around theV upper end of the boss'33. The discs are larger than the inside diameter of the tube Yso that a pressure sealing ii-t results. Due Vto the flexibility of the sealing disc material, this oversize, for examplqcan be as much as ,012.5 Ato .Q19 inch onaside. Y l A f Sandwiched between the stack'o'f d iscs andthe end cap member Y2,8,Y is a rigid backing disc 47 of plastic or metal which extendsY ingclosely spaced relation to the walls of the tube 10, this spacing being sufiicientiy large to provide suflicient clearance for passage of a requisite amount of Vair for good pumping action but suiciently small that the periphery oftheV stack of valve'rdiscs will not be so nexible that Vthey readily bend intorthe space. It should be noted that flenibility of the stack of discs considered as a whole is substantially less than the discs individually since eachV is backed up Yby Vthe adjacent disc and thepri'gid backing disc 47 The valve discsmake pressure sealing sliding engagernent With fthe Walls of the tube 10u/hen the plunger Ytube is pushedrdown `(Fig.7v3)`and With only aY smallamount `of ldrag andV readily fflex' downwardlytfig. 2) to open the valve and allow air to pass therearoundj annular air-intake passage 22 therebetween; A'l`hevery topV Vof lthe plunger tube is Vexternally threaded asV at 24 to threadedlyreceive a closure cap 25, andthe bottoni of Ythe plunger/tube is closed by an end cap and valve assembly` 26. Theend cap assembly comprises'an end cap member `23 which is'preferablyfmade ofV theV Vsame material as tube vlZ'and has a cylindrical skirt portion Y 3i) deninga valve seat recess 3l, the skirt portion 4fitting Vwithin the plunger tube and preferably cemented to the inner walls thereof. The end cap member has a hanged Y portion 32 which underlies the end of the plunger tube.

which Vopens onto the center portion of the larger valveseatv-recess 31. VThe boss 33 also has a central bore 33' which extends'from the bottom surface of the boss to ExtendingV freely through the boss bore 33 and the well 34 fandterminating within the valve seat recess '31 Y is a'val've Vstem 35 made of metal VorY other suitable The following'are examples of valve'discs which give excellent sealing qualities `with, only slight frifctionalV drag where the inside diameter of they outer Vtube lli) has a Vtolerance of'frorn 1.406 inches to vl.4ll"inches and the discs have `an oversize of vfrom `.0125 inch to .019 inch l from the inner walls of outer tube 10: Y

(i) a Stack sf three discs each ofv a aneignen Aor .007 inch, fr Y Y. Y. Y

v (2) a stackA of four'di'scs each ofathickness ofV .006 inch,

ness Yof.005 inchf (themostpreferred,arrangementfisa s'tackof siXdiscsLand i il, Y'

(4) a stack ofrse'ven or Veightfdiscs each of a thickness ofllinch.' 'Y 'i Secured upon the-inverted 'cupshaped member 38.is a rubber Washer 57YV Whichfngalgesthe bottom. :of the end cap boss 33 when thevalve stemis pushed upwardly V(3) aV stack of from four to siiiV discs eachlof a thick- Y acadien.

walls of Vbore as and the valve stem 35 into pumping space 16, should the operator lean against the plunger tube. (The latter clearance space normally enables the slow leakage of material from the well 34 into the pumping space during the upward movement of the v plunger tube.)

Referring now to the construction of the outer tube 1t), this tube is provided at its top with an annular sleeve member 66 made of preferably the same material as the tube 1@ itself, which sleeve is cemented to lthe latter tube. The sleeve 6d has an inwardly extending portion 62 which overlaps and extends a small distance beyond the inner surface of the tube it) to extend contiguous to the plunger tube, but with a small air passage space provided therebetween, to provide support for the plunger tube.

The bottom end of t te outer tube is provided with a pair of axially-spaced, bathe-forming transverse walls 65-67. These walls have confronting peripheral flanges 69-71 which are cemented together and to the bottom edge of the outer tube. These walls may be made of a material similar to that out of which the outer tube is made. The innermost or uppermost wall 65 has a circumferential opening or slot 73 adjacent its perimeter and the lowermost or outermost wall 69 has a similar circumferential slot or opening 75 located contiguous to its perimeter at a point diametrically opposite the slot 73. in this manner, a tortuous path for the flow of air and material to be sprayed is provided between the pumping space 16 and the slot 75 of the outermost wall 67.

Covering the bathe-forming walls is the above mentioned dome-shaped end cap 29 of the outer tube which may be made of the same material as tube 10. This end cap has a hat bottom or end portion 77 of a much smaller size than the diameter of the outer tube and a frusto-conical wall portion 79 extending upwardly and outwardly from the dat bottom 77 annd terminating in a generally cylindrical skirt portion 31 having a radially projecting portion S3 at one point thereon. The frustoconical wall 79 contains the aforementioned discharge orifice 1S which is located at the same circumferential position as the radial projection 233 of the end cap and the center line of the circumferential slot 73 of the uppermost or innermost bathe-forming wall 65. rfhe radial projection 83 indicates to the operator the location of the discharge orifice i8 so that he may properly position the spray gun to discharge the spray in the proper direction.

In order to fan out the uid stream discharging from the orice 18, a deector lip 85 is preferably formed integrally with the body of end cap Z5* above the discharge orifice. The deflector lip SS has a concave inner surface S7 against which the emerging stream of fluid impinges and deflects laterally outwardly.

The dome-shaped end cap member 2i) defines an unobstructed space 88 therein of generally the same shape as the end cap member itself. The inner surfaces 89-9il thereof denne the extremities of the Space SS and aid in guiding the mixture of air and liquid from the opening 75 in the wall 67 to the discharge orifice 18.

The baile wall design just described is particularly useful in the spraying of liquid materials since the space dened between the walls 65 and 67 aids greatly in mixing the liquid and air.

The operation of the sprayer of the invention is as follows: When the plunger tube 12 is telescoped within the outer tube near but not quite to its fullest extent, the cup-shaped member 38 at the bottom of the plunger tube makes contact with the uppermost bathe wall to place the spring 41 under compression. The plunger tube then moves downward a small amount until the bottom of the boss 33 of the end cap member 28 touches the top of the rubber gasket 57 to seal oif the clearance space between the valve stem 35 and the bore 33. In this position of the plunger tube, the valve head 36 is spaced d from the top of the well 34 so that the materiai to be sprayed within the plunger tube quickly fills the well 34. As the plunger tube is pulled upwardly within the outer tube, the spring 41 expands and presses the cupshaped member 38 downward to bring the valve head 36 tightly around the well 34 thereby sealing off the well rom the supply compartment within the plunger tube. The material then in the well 34 slowly leaks through the clearance between the defining walls of the bore 33 and valve stem 35 into the pumping space 16 beneath the plunger tube. Withdrawing the plunger tube from the outer tube reduces the pressure in the pumping space 16 substantially below atmospheric pressure so that air is drawn into the pumping space through the clearance between the plunger tube and the sleeve 3@ in the main body of the outer tube. The dierential pressure existing between pumping space 16 and the annular clearance space 22 above the valve disc assembly 28 is sufficient to deform or force the peripheral portions of the disc assembly downwardly, as shown in Fig. 2, to enable passage of air into the pumping space 16. A much smaller quantity of air enters the pumping space 16 through the discharge orifice 13 in the bottom of the outer tube 1G, but this air moving quickly aids in unclogging the passages leading to the pumping space and in creating a turbulence which aids in mixing the material to be sprayed and the air. Thus, the gradual dropping of the material in the well 34 into the pumping space 16 together with the sucking of air into the pumping space greatly aids in admixing the material to be sprayed and the air. Additionally, the degree of upward movement imparted to the plunger tube is a function of the concentration of the spray desired. The Ureater the upward movement, the greater the amount of air sucked into the pumping space 16 and therefore the less concentrated is the atomized spray issuing from the discharge orifice upon the downward stroke of the plunger tube.

Upon downward movement of the plunger tube, pressure builds up in the pumping space 16 which forces the peripheral portions of the valve disc assembly 15 tightly against the inner walls of the outer tube to form an airtight seal therewith. The spring 41 is preferably selected so that it will give a little (i.e. not enough to result in any leakage of material from the plunger tube) under this pressure so that air under pressure will leak under the valve head 36 and into the plunger tube raising the pressure therein. The compression stroke, of course, also forces the mixture of air and the material to be sprayed through the path indicated by the arrows. This path extends through the opening or openings in the bathe walls and then along the sides of the space 88 formed within the dome-shaped end cap 20 following a generally tortuous path to the discharge orifice 18. The tortuous path creates a turbulence which greatly increases the intermixture of the air and the material to be sprayed and hence the degree of atomization of the latter material. As the mixture passes through the discharge orifice, it strikes the deflector lip and fans outwardly, as shown most clearly in Fig. 1.

.As previously indicated, the sealing unit of the present invention is applicable not only as a one-way valve, but also as a sealing unit which seals in both directions of movement of the piston or plunger involved and also as a stationary packing gland for making sealing engagement with a reciprocating member, such as a piston or plunger rod. These applications of the invention are illustrated in Figs. 7-9 which show a reciprocating device 91 having an outer tubular member 10 defining a plunger bore in which is reciprocally mounted a plunger 93 operated by a rod 95 extending through an opening 97 in the center of a cap 99 suitably @ed over the open top of the outer tube 10.

The plunger 93 has a circular disc-shaped bottom portion 101 having an upstanding cylindrical neck 103 provided with an upwardly facing bore 105 which threadsembly previously described in connection with the em# bodixnent of Figs; l-6. `The perimeter of the plunger portion 101 is spaced from the inner Walls of the outer tube 10', for example, in the neighborhood of from .02()V to .030 inch, preferably from .022 to .024r inch. A disc retainer cap 111 is provided on top of the disc assembly 169, the retainer cap 111 comprising a flat bottom portion 113Y of the same diameter as the bottom portion 191 of the plunger, and a hollow upstanding neck portion 115 tting around'the top of the neck portion 163 of the plunger, The retainer cap is held in place by a snap ring Y117 sandwiched between the Yupper end ofthe neck portion 115 of the retainer cap and a downwardly facing shoulder 119 provided by the reduced'end 1697 pf the plunger rod 95.

The disc assembly is thus backed up on both sides so that the assembly seals in both directions of movement ofthe plunger. The frictional drag offered by the'disc assembly is such that Vthe operating rod may be operated by hand where the back pressures areV ofV a similar order Y to that offered bythe sprayer device shown in Figs. 1*-5.

The cap 99 Vat Vthe top of the outer tube 1?" carriesV Vva packing gland generally indicated by reference numeral 121Which comprises aV stack orf'flat,i wafer-like ,sealing discs 122 of polyethylene or similar material. These discs provide a pressure seal between-the defining walls of cen-- ter holes 123Y'and the'operating rod 95. The diameter of the latter holes maybe undersized'with'respect to the op? erating rod, for example, inthe neighborhood of from .007'V ,to ,015 inch, assuming 6 discs each of .G06 inch thick.

tendinginwardly from a depending skirt 129 f thec'ap 99 and the top walll131thereof. VEach projecti0n'127 has an axially sloping'upper surface 133, 'the'upperrriost' portion. ofrwhich is spaced from'the Vbottom of thetop wall 131 an amount somewhat less thanrthe thickness of the stack of sealing discs 1,22Y and the backing disc 126,

Y so that the discs can be wedged or pammed securely in.VY place between cap wall V131 and the cap projections '127, YThe operating rod 95 passes through the central opening 97 in the cap top wall, and the defining walls of theV latter opening are `spaced the same distance from the operating rod as the defining walls of the central opening 12,5"of

the backing disc 126.YV

' .The inner diameter Yofthe skirt 129 from which ythe Y pass behind the Yprojections 127. HolesV 135 are prn-l V vided in eaehdi'sc 122 and the backing discV 125 to reff1 I ceivea 4-pronged tool (not'shown) by means of which the stack of discs can be rotated and forced into place behind the projections 127. e f

The'backingdisc 12.6 prevents the `downward flexure Y ofthe sealing discs. To Vthis end, the detining walls'of thercentral'opening 126'V .of the backing disc arej spaced from thefoper'ating rod, for example, inthe'neighber-` Vhoodof from .OlQit'o .015 inch or less. Y

Inl each of the'applications of the present invention den scribed above, the disc assembly provides a slippery, low

frictional drag; surface which makes a highlyeifective pressure seal between two relatively'movablelreciprocating members. In one application ofthe invention, the A disc assembly provides a seali-n both directions of movement of the lreciprocating member and, in another ap-Y plication ofthe invention, acts as a one-way valve in V,one direction of'movement of the reciprocating member and as a pressure seal in the other direction of movement thereof. Y Y

`It should be understood that numerous modiiicati'ons` may be made of the preferred forms of the invention above described without Vdeviating from the broader aspectsiof the invention. Y Y Y What Iclaim as new anddesire to protect byLetters Patent of the United States is: Y Y

l. In a handaoperated Aspraygun ofthe type having an outer member 'in which a `plunger is mounted for manual reciprocation in a plunger bore towardV and away from a pumping space to which the material to be sprayed is fed, there being an annular airrpassage space between said plunger and the dening Walls of said plunger bore into which air is drawn bysuction during the rearward stroke` of said plunger, the improvement in alone-way valve carried by said plunger which valve sealsoff said annular passage space from said pumping space'during the forward or compression stroke of said plunger and provides an opening between said annular air passage space and said pumping space during the rearwardistroke thereof for directing appreciable quantities of air tosaid Y pumping space comprising: a stack of wafer-like valve.- Y forming discs each having the thinness of iilm and made being forwardly exible, the peripheral edges of said stackV of discs making free sliding,V air sealingfrengagement with Ythe walls of said plunger bore duringthe forward or compression strokeof said'plunger and being flexedforward-Y ly during the rearward stroke ofthe plunger due to the reduced pressure then existing in said pumping space, whereby air is sucked into said pumping spacer.V

2.A In a hand-operatedrspray'gu'n of the type having an I outer membery in whicha plunger is mounted 4for manual reciprocationiin aplunger bore toward and away from a pumping space to which the material to be sprayed is fed, there being an annular air passage space between said plunger andthe defining walls of said plunger bore into which air is drawn by suction during the rearward stroke 5f;v of`s`aid plunger, the improvement'in a one-way valve carried by said plunger which valve seals o saidannular passage space from said pumping space during the forward or compression stroke of said plunger and provides an opening between said annular air passage space and 5`5` said pumping space during the rearward stroke thereof for directing appreciable quantities of air to said pumping space comprising; a stack of wafer-like valve-forming discs each having the thinness of film and made of polyethyleneV material secured to said .plungern'eare'st said 31j pumping space and being of a size slightly greater than said plunger bore and the peripheral portionsV thereof being forwardly exible, the peripheral edges of said 'stack of discs making free sliding, Yair sealing engagementV with the walls of said plunger Vbore duringrthe forward or compres- 5' sion stroke of said plunger and'being flexed forwardly Y Vduring the rearward stroke of the plunger dueto the reduced `pressure then existing Y in said pumping space, Vwhereby air is sucked Vinto said pumping space. 1 Y 3. In a hand-operated spray gun of the type having an 76 outer member in which a plunger istmounted vfor manual reciprocation in a plunger bore toward and away from a pumping space to which the material to be sprayed'is fed, Y therebeing an`annular 'air passagespace between said Y plunger and the defining walls of said plunger bore into Vwhich-air is drawn by suction during the rearward stroke of said plunger, the improvement in a one-way valve carried by said plunger which valve seals off said annular passage space from said pumping space during the forward or compression stroke of said plunger and provides an opening between said annular air passage space and said pumping space during the rearward stroke thereof for directing appreciable quantities of air to said pumping space comprising: a stack of wafer-like valve-forming discs each having the thinness of iilm and made of flexible wear-resistant, slippery material secured to the end of said plunger nearest said pumping space and being of a size somewhat greater than said plunger bore to provide a sealing, sliding t therewith, means on the end of said plunger providing a forwardly facing shoulder against which the central portion of said stack bears, means forcing the central portion of said stack of discs against said shoulder, the peripheral portions of said discs being forwardly flexible, the peripheral edges of said stack of discs making free sliding, air sealing engagement with the walls of said plunger bore during the forward or compression stroke of said plunger and being flexed forwardly during the rearward stroke of the plunger due to the reduced pressure then existing in said pumping space, whereby air is sucked into said pumping space.

4. A hand-operated pumping device comprising: an outer member in which a plunger is mounted for manual reciprocation in a plunger bore toward and away from a pumping space, there being an annular passage space between said plunger and the dening walls of said plunger bore through which a uid to be pumped is drawn by suction during the rearward stroke of said plunger, a one-Way Valve carried by said plunger which valve seals oif said annular passage space from said pumping space during the forward or compression stroke of said plunger and provides an opening between said annular air passage space and said pumping space during the rearward stroke thereof for directing appreciable quantities of the uid to be pumped into said pumping space, said one-Way valve comprising: a stack of very thin, at, wafer-like valve-forming members carried by the plunger and each having the thinness of lm and made of a iiexible slippery material and being of a size greater than said plunger bore ,to provide pressure sealing, sliding engagement with the dening walls thereof, means on said plunger forming a forwardly facing backing shoulder against which said valve-forming members bear, the perimeter of said backing shoulder contiguous to but spaced from the defining walls of the plunger bore to provide a support backing for the peripheral portions of the stack of valve-forming members and which prevents substantial rearward flexing thereof as a whole during the forward stroke of the plunger, so as to provide a pressure seal between the plunger and said plunger bore walls, and the peripheral portions of said valve-forming members being free to ex forwardly during the rearward stroke of the plunger due to the reduced pressure then existing in said pumping space, whereby said Huid is sucked into said pumping space.

5. In an apparatus having a reciprocating member movable with respect to a guiding wall surface, sealing means carried by one of said reciprocating members and guiding wall Surface and making free sliding, pressure sealing engagement with the other of same and comprising: a stack of flat wafer-like members having the thinness of lm, the longitudinal axis of which is parallel to the direction of movement of said reciprocating member, each of said wafer-like members being made of a ilexible slippery material, and rigid backing means on at least one end of said stack for preventing appreciable axial exure of the said wafer-like members in at least one axial direction.

6. In an apparatus having a reciprocating member movable with respect to a guiding wall surface, sealing means carried by one of said reciprocating members and guiding wall surface and making free sliding, pressure sealing engagement with the other of same and comprising: a stack of flat Wafer-like, polyethylene members having the thinness of lilrn, the longitudinal axis of which is parallel to the direction of movement of said reciprocating member, and rigid backing means on at least one end of said stack for preventing appreciable axial ilexure of the said wafer-like members in at least one axial direction.

7. In an apparatus having a reciprocating member movable with respect to a guiding wall surface, sealing means carried by one of said reciprocating members and guiding wall surface and making free sliding, pressure sealing engagement with the other of same and comprising: a stack of flat Wafer-like members having the thinness of lm, the longitudinal axis of which is parallel to the direction of movement of said reciprocating member, each of said Wafer-like members being made of a flexible slippery material, and rigid backing means on only one end of said stack for preventing appreciable axial flexure of the said wafer-like members in only one axial direction, said stack of wafer-like members being free to llex axially in the other direction so as to form a one-way valve.

8. In an apparatus having a reciprocating member movable with respect to a guiding wall surface, sealing means carried by one of said reciprocating members and guiding wall surface and making free sliding, pressure sealing engagement with the other of same and comprising: a stack of flat wafer-like members having the thinness of film, the longitudinal axis of which is parallel to the direction of movement of said reciprocating member, each of said Wafer-like members being made of a flexible slippery material, and rigid backing means on both ends of said stack for preventing appreciable axial flexure of the said wafer-like members in both axial directions.

9. In an apparatus having a reciprocating member passing through an opening in a casing member, a packing gland carried by said casing and surrounding said reciprocating member at the point of entry into said casing member and making free sliding, pressure sealing engagement with the periphery of said reciprocating member, said packing gland comprising: a stack of wafer-like members having the thinness of lm, the longitudinal axis of which is parallel to the direction of movement of said reciprocating member, each of same Wafer-like members being made of a ilexible material, and rigid backing means on both ends of said stack for preventing appreciable axial ilexure of said Wafer-like members in both axial directions.

10. An outer member having a plunger bore therein, a plunger mounted for reciprocation in said bore, sealing means carried by said plunger which seals oi the space between the plunger and the defining walls of said plunger bore during at least one direction of movement of said plunger, said sealing means comprising: a stack of waferlike members having the thinness of film and each made of flexible material and being of a size somewhat greater than said plunger bore lto provide pressure sealing sliding engagement with the defining walls of said plunger bore, means on said plunger forming a backing shoulder for at least one end of said stack of wafer-like members, and the perimeter of said backing shoulder being closely spaced from the defining walls of the plunger bore, to provide a support backing for the peripheral portions of said wafer-like members which prevents substantial ilexing of the stack as a whole during the movement of said plunger in one direction.

References Cited in the iile of this patent UNITED STATES PATENTS 2,399,550 Klien Aug. 30, 1946 FOREIGN PATENTS 920,943 France Jan. 8, 1947 

